In addition to the DVI to MDP converter box, it ought to be possible to use a simple cable to convert normal DP to the MBP used by the LED Cinema Display. I'm unaware of a cable to do so at present, though.

ATi's new Eyefinity cards will come with MDP sockets, although I expect them to cost a lot since they are "enthusiast" level card, great for games and being able to drive 6 seperate displays.

I know when it came out it was impossible to connect it to anything other than MacBooks that had mini DisplayPorts. I don't think there are a lot of PCs with mini DisplayPorts out there; it might be kind of hard.